fergbrain

Forces new users to register additional fields. Available fields are:
<ul>
<li>First Name</li>
<li>Last Name</li>
<li>Nickname</li>
<li>AIM screen name</li>
<li>Yahoo IM screen name</li>
<li>Jabber/Google Talk user name</li>
</ul>

Force User Field Registration

Forces new users to register additional fields (such as first name and last name). Note: WordPress 2.5 or higher is definite required due to new erro …

Jason Coleman

Paid Memberships Pro

Kim Coleman

Andrew Lima

This plugin hides the “Display Name” field on the Edit Profile screen for all users. Instead of allowing users to set this field, the plugin will always set the User field display_name to their first and last name. If these field are empty, display_name will be set to their username.
Display names are set when the user registers as well as when a user’s profile is updated via the WordPress admin.
The plugin includes a batch process to update the display name for existing users. Navigate to Settings > Force First Last in the WordPress admin to run the update.

Force First and Last Name as Display Name

Thank you for this simple and effective solution. It is something that should be part of WordPress by default.
Cheers

Simple and effective

Force the user field "display_name" to be set as the user's first and last name.

Force User Field Registration vs Force First and Last Name as Display Name